KR20110081877A - Mimo-based multiple base station collaborative communication method and apparatus - Google Patents

Abstract

A solution for multiple base station cooperative communication in TDD (time division duplex) and FDD (frequency division duplex) systems is provided. The serving base station and the coordinating base station transmit detection signals according to certain multiple input multiple output (MIMO) features with one or a plurality of communication resources. The mobile station measures the detection signals with one or a plurality of communication resources and generates indication information of the recommended cooperative communication modes based on the measurement results. Preferably, sequence numbers of time-frequency resources corresponding to the recommended cooperative communication modes are reported to the serving base station. The serving base station then schedules at least one of the one or the plurality of mobile stations according to the indication information reported by the one or the plurality of mobile stations and provides a MIMO communication mode for the scheduled mobile station. By utilizing the invention, coverage of cells is improved, cell edge user throughput is increased and inter-cell interference between neighboring base stations is reduced. Advantageously, the amount of uplink feedback information is reduced and uplink bandwidth is saved.

Description

MIMO-BASED MULTIPLE BASE STATION COLLABORATIVE COMMUNICATION METHOD AND APPARATUS

TECHNICAL FIELD The present invention relates to wireless communication networks, and in particular, to a method and apparatus for MIMO-based multiple base station cooperative communication.

In order to improve the performance of single-user MIMO (multi-input multiple output) and multi-user MIMO, Alcatel-Lucent Company and others have invented a multi-BS (base station) cooperative method. Its basic idea is to transmit and receive MIMO in cooperation between multiple BSs and one or more mobile stations (MS) with the same radio resources. This technique has basic features in two aspects.

1) Multiple BSs may serve one or more MSs with the same time-frequency resources through coordination between BSs.

2) Each BS can serve one or more MSs with the same time-frequency resources.

In the multi-BS collaborative MIMO method, each BS needs to set up the best cooperation and design the optimal MIMO transmission method according to the channel information of all serving MSs. Obtaining downlink channel information can be realized in the following other ways.

i. In a time-division duplex (TDD) system, the BS can obtain an uplink channel fading response over an uplink sounding signal or uplink traffic channels due to the interdependence between the uplink channel and the downlink channel of the TDD system. . Uplink channel estimation may be used to approximate the channel state information of the downlink, wherein the time interval between uplink and downlink transmissions is less than the coherence time.

ii. For FDD (frequency-division duplex), the downlink channel fading response has little to do with the uplink channel fading response, since the frequency spacing between the uplink channel and the downlink channel generally exceeds the channel coherent bandwidth. Thus, it is impossible to track channel state information of the downlink based on the uplink channel response.

Therefore, in an FDD system, channel state information can be obtained through how each MS feeds downlink channel coefficients to the BS, or downlink channel information can be obtained by each MS calculating a plurality of codebooks and selecting the best one therefrom. And then return the channel's index and SINR (signal to interference and noise ratio) to the BS.

The drawback of the described method i is that it can only be applied to TDD systems and not to FDD systems.

In addition, the drawback of the described method ii is that the amount of feedback of the terminals is enormous and the uplink channel resources are occupied limited in the way in which the downlink channel coefficients are fed back, and in the method in which the codebooks are calculated, the computational complexity of the terminals is large.

In order to solve the existing problem described above in the prior art, the present invention provides a solution suitable for multi-BS cooperative communication in both TDD and FDD systems. In particular, it coordinates with the serving BS (the BS that registered when the MS was turned on to access the network, or the target BS that is newly connected by the MS when performing handover between cells) and the coordinating BS (the serving BS to serve the MSs). The coordination BS) sends detection signals in accordance with certain MIMO features and specific beam signals used for detection with one or more communication resources. The MS measures the detection signals with one or more communication resources and generates indication information of the recommended cooperative communication modes based on the measurement results. Preferably, the indices of time-frequency resources corresponding to the recommended cooperative communication modes are reported to the serving base station. The serving base station then schedules at least one of the one or more MSs according to the indication information reported by the one or more MSs and provides a MIMO communication scheme for the at least one scheduled MS.

According to a first aspect of the present invention, a method for providing a communication scheme to one or more mobile stations served by a serving base station in a serving base station of a MIMO-based wireless communication network, each of the one or more mobile resources with one or more communication resources. Sending one or more first detection signals according to respective MIMO features; Obtaining indication information used from the one or more mobile stations for indicating information related to the communication resources and / or MIMO features corresponding to recommended cooperative communication modes recommended by the one or more mobile stations; And scheduling at least one mobile station of the one or more mobile stations according to the indication information and providing a MIMO communication scheme for the at least one scheduled mobile station.

According to a second aspect of the present invention, there is provided a method for assisting a serving base station to provide a communication scheme for a mobile station served by coordination by a coordination base station in a MIMO-based wireless communication network, according to MIMO features. Providing one or more second detection signals to the one or more mobile stations as one or more communication resources.

According to a third aspect of the present invention, there is provided a method of assisting a serving base station for providing a communication scheme to a mobile station in a mobile station of a MIMO-based wireless communication network, comprising: at least one according to MIMO features sent to one or more communication resources; Obtaining detection signals from one or more base stations including the serving base station; Measuring a signal strength of at least one of the detection signals according to MIMO features sent by one or more base stations to at least one of the one or more communication resources; And one or more indication information used to indicate information related to the communication resources and / or MIMO features corresponding to one or more recommended cooperative communication modes recommended by the mobile station, according to the measured signal strength. A method is provided, comprising generating indication information.

A first providing apparatus for providing a communication scheme to one or more mobile stations served by a serving base station in a serving base station of a MIMO-based wireless communication network, in accordance with a fourth aspect of the present invention, comprising: First signal transmitting means for respectively sending one or more first detection signals in accordance with respective MIMO features to the one or more mobile stations; Indication information obtaining means for obtaining from said one or more mobile stations information relating to said communication resources and / or indication information used for indicating MIMO features corresponding to recommended cooperative communication modes recommended by said one or more mobile stations; ; And second providing means for scheduling at least one mobile station of the one or more mobile stations according to the indication information and providing a MIMO communication scheme for the at least one scheduled mobile station.

According to a fifth aspect of the present invention, there is provided a first aiding apparatus for assisting a serving base station to provide a communication scheme for a mobile station served by the coordination base station to the coordination base station of the MIMO-based wireless communication network. A first assistance apparatus is provided, comprising second signal transmission means for sending one or more second detection signals in accordance with features to the one or more mobile stations as one or more communication resources.

According to a sixth aspect of the invention, there is provided a second aiding apparatus for assisting a serving base station for providing a communication scheme to a mobile station at a mobile station in a MIMO-based wireless communication network, comprising: MIMO features sent to one or more communication resources; Signal acquiring means for obtaining at least one detection signal according to, from one or more base stations including the serving base station; Measuring means for measuring a signal strength of at least one of the detection signals in accordance with MIMO features sent by one or more base stations to at least one of the one or more communication resources; And one or more indication information used to indicate information related to the communication resources and / or MIMO features corresponding to one or more recommended cooperative communication modes recommended by the mobile station, according to the measured signal strength. A second aiding apparatus is provided, comprising instruction information generating means for generating instruction information.

Advantages of the present invention include the following.

i) Possible for both FDD and TDD systems.

ii) preferably in the indication information sent by the MS, the MS feeds back the index of the time-frequency resource corresponding to the appropriate multi-BS cooperative communication and the communication scheme in which at least one coordinating BS of the multiple BSs suppresses interference to the MS; Just do it. The MS does not need to feed back channel coefficients between this and the serving BS and channel coefficients between the MS and the coordinating BSs. Therefore, the amount of uplink feedback information is reduced and the uplink bandwidth is saved.

iii) improved throughput for extended cell coverage and cell edge users;

iv) Reduced intercell interference (ICI) for neighbor BSs.

Other features, objects, and advantages of the present invention will become more apparent with reference to the following detailed description of non-limiting embodiments.

1 is a schematic diagram of a multi-BS cooperative MIMO in a wireless communication network in accordance with an embodiment of the present invention;
2 illustrates an example where a plurality of BSs send a plurality of opportunistic beamforming detection signals according to an embodiment of the invention.
3 illustrates an example of sending a plurality of opportunistic beamforming detection signals by adjusting a plurality of BSs according to an embodiment of the present invention.
4A shows a no. Schematic diagram in which the MS 4 detects opportunistic beamforming signals from a plurality of BSs in one time-frequency block.
4B is No. Schematic diagram in which the MS 4 detects opportunistic beamforming signals from a plurality of BSs in two time-frequency blocks.
FIG. 5 shows a first providing apparatus 10 to a serving BS 1, assistance BSs 2, 3 to perform MIMO-based multi-BS cooperative communication in a wireless communication network according to an embodiment of the present invention. A block diagram of the first aiding device 20 and the second aiding device 30 to the MS 4 is shown.

The same reference numeral is used for the same device (modules) or steps.

1 is a schematic diagram of a multi-BS cooperative MIMO in a wireless communication network according to an embodiment of the present invention. In FIG. 1, the MS 4 is cooperatively serviced by the BS 1, BS 2 and BS 3. Since the MS 4 registers with the BS 1, for example, the MS 4 registers with the BS 1 when it is turned on and accesses the network, or when the MS performs handover between cells, The target BS to which 4) is newly accessed is the BS 1. Therefore, BS 1 is the BS used for MS 4. When the MS 4 is placed in a position adjacent to the cell edges of the BS 2 and the BS 3, the serving BS 1 interacts with the control commands with the BS 2 and the BS 3. BS 1 instructs BS 2 and BS 3 to cooperate with BS 1 and completes communication with MS 4. Accordingly, BS 2 and BS 3 become coordinating BSs of MS 4. On the other hand, the BS 1 also services the MS 5. BS 1 applies MS-MIMO (Multi-User Multiple Input Multiple Output) method to avoid or minimize multi-user interference between MS 4 and MS 5 by Serving). BS 2 and BS 3 serve MS 4 by applying SU-MIMO (single-user multiple input multiple output).

2 and 1, a flowchart of the systematic method of the present invention is described in detail. 2 is a flowchart of a systematic method according to an embodiment of the present invention. As follows, the case of communication between BS 1, BS 2, BS 3 and MS 4, MS 5 has been taken as an example to describe an embodiment of the present invention.

First, in step S100, the MS 4 determines BS 1 as its serving BS. When turned on to access the network, the MS 4 registers the relevant information with the BS 1, so that the BS 1 becomes the serving BS of the MS 4, or in another case, the MS When performing a handover between the MSs, the MS 4 moves from its home cell to the neighbor cell to set up communication with the target BS 1 in the neighbor cell. Accordingly, BS 1 becomes the serving BS of MS 4. Similarly, MS 5 determines BS 1 as its serving BS. It will be appreciated that in the actual network configuration, the BS can serve one or more MSs, although the MS 4 and the MS 5 are shown for convenience of illustration only as two MSs served by the BS 1. Certainly, the present invention can be applied to the BS 1 serving multiple MSs.

Subsequently, in step S101, the BS 1 instructs the MS 4 and the MS 5 served by the BS 1 to measure and report channel related information. In particular, BS 1 allocates uplink control channels for MS 4 and MS 5 and MS 4 and MS 5 report the measurement results of their channel related information to this control channel. Set conditions to report channel related report information.

In step S102, the MSs 4 and 5 each measure channel related information to generate channel related report information. In particular, the channel related report information may include channel quality related information, for example, RSSI (received signal strength indicator), CINR (carrier interference to noise ratio), or CQI (channel quality indicator), and also MS Location information, for example, DoA (reach direction) or AoA (reach angle) of the MS.

Since there is no need to process and demodulate the received sampled signals, estimating RSSI is easier and the computation is not too complex. However, received signals on the one hand also include noise, interference and other channel loss, so that the received signals are strong does not mean that the channel and signal quality are good, but only that there are only strong signals in the channel.

CINR (or SNR or SINR) provides information on how strong the desired signals are relative to interference (or noise or interference and noise). Most wireless communication systems are limited to interference, so CIR and CINR are generally more applicable. Compared to RSSI, these measurement results provide a more accurate and reliable estimate, but the cost is more complex calculations and extra delays. The CINR can be estimated by estimating signal power and interference power, respectively, and then obtaining the ratio of the two values. This channel parameter can be used to calculate the signal power.

It is known to those skilled in the art how MSs make measurements of RSSI, CINR, CQI and DoA. Accordingly, the present invention will not be described here.

The MSs 4, 5 can measure channel related information between them and the serving BS, i. E. BS 1, and not only the channel related report information but also these and other BSs, e.g. BSs 2, 3 Channel-related information can be measured.

Subsequently, in step S103, the MSs 4 and 5 may determine the respective channel related report information for the BS 1, or the channel related report information conditions set by the BS 1 for the BS 1, respectively. Provides report information related to channels that are satisfactory.

In another embodiment, MSs 4 and 5 have already obtained command information from BS 1 in advance. That is, the MSs 4 and 5 already know the control channel and the conditions under which the channel related report information should be reported to the BS 1. Therefore, for example, steps S100 to S102 may be omitted, and the MSs 4 and 5 periodically report their channel related report information to the BS 1.

Then, in step S104, according to the report results of the channel related report information of the one or more MSs served by the BS 1, the BS 1 makes a request to send detection signals according to specific MIMO features. Send to neighbor neighbor BSs. In this embodiment, these detection signals according to certain MIMO features are considered as opportunistic beamforming detection signals to use as an example to illustrate the present invention.

In particular, in step S104, in accordance with the obtained channel related report information of the plurality of MSs, including the channel related information obtained from the MS 4 and the MS 5 in step S103, respectively, the BS 1 is multi- Determine which MS needs to be served in the BS cooperative MIMO scheme and which BSs to set up the cooperative MIMO scheme. Once the multi-BS cooperative MIMO scheme is selected, the serving BS 1 must send a request for an opportunity beamforming detection signal to certain neighboring BSs. In this embodiment, the serving BS 1 is served by the MS 4 in such a way that the collaborative MIMO is set up with the BS 2 and BS 3 while the MS 5 is serviced in a non-cooperative MIMO manner. Decide to be. In this embodiment, the serving BS 1 simultaneously selects the serving MS 4 and the MS 5 with the same time-frequency resources. Accordingly, the conventional single-BS multi-user MIMO scheme has been established between BS 1, MS 4, and MS 5. The principle of operation of the multi-BS cooperative MIMO of the present invention will be described next using the MS 4 as an example. MS 5 will not be described.

Subsequently, in step S105, each described requested BS decides whether to accept the opportunistic beamforming detection signal sending request with the BS 1 initiated by the BS 1, according to information such as resource occupancy status. do. In this embodiment, BS 2 and BS 3 send decision information to BS 1 to determine to send opportunistic beamforming detection signals in cooperation with BS 1.

When BS 1 obtains a request from one or more neighboring BSs, for example BS 2 and BS 3, to accept beamforming detection signal transmission, BS 1 in step S106 has an opportunity. Instructs coordinating BS 2 and BS 3 to send enemy beamforming detection signals.

 Preferably, in step S106, BS 1 adjusts which specific beams should be sent with specific time-frequency resources in order to point out or not point out specific MSs or to send random beams. ) Further instructions. Therefore, coordinating BSs 2, 3 obtain indication information from BS 1 with which time-frequency resources in which direction the beams will be sent. For example, BS 1 is No. Instruct BSs 2 and 3 to send opportunistic beamforming detection signals 2B and 3A in one time-frequency block, respectively, hoping to point or not point to MS 4. Instruct BSs 2 and 3 to send opportunistic beamforming detection signals 2A and 3C in two time-frequency blocks, respectively.

Subsequently, in step 107, serving BS 1 and coordinating BSs 2, 3 simultaneously send opportunistic beamforming detection signals to a particular time-frequency block.

The transmission process of the beam signals by the BSs 1, 2, 3 will be described in detail as follows. 3 describes an example where a plurality of BSs send a plurality of opportunistic beamforming detection signals equally. The basic idea of so-called opportunistic beamforming is that the throughput of the system can be maximized by assigning channels preferably to users who can almost certainly complete continuous transmission. For reflective spatial channels, the opportunistic beamforming method can point out users with the largest SINR, whereas in the case of sufficient scattering, the opportunistic mechanism will assign channels to users with the largest instantaneous capacity. will be.

In this embodiment, each cell is divided into three sectors as shown in FIG. Each sector is 120 degrees. Here BS 1 is located in the center of the cell, which corresponds to a sector having 120 degrees in the cell. The BS 1 can send beams in six kinds of directions. The six beams were indicated as 1A-1F clockwise, respectively. Not all reference signs of the beams are indicated in view of the paper space limitations. It will be appreciated that the sector may correspond to eight beams or some other beams and may be configured by the BS serving this sector. Thus, as an example, BS 2 sends beams in six types of directions, clockwise arranged, indicated by 2A to 2F in the sector served by BS 2. The BS 3 also sends beams in six directions, arranged in a clockwise direction, indicated by 3A to 3F in the sector served by the BS 3.

In this embodiment, all sectors are divided into parts A, B and C as three parts, respectively. Each part contains several non-neighboring sectors. Sectors served by BS 1 are located in part A, sectors served by BS 2 are located in part B, and sectors served by BS 3 are part C My location is BSs belonging to different parts may send beam detection signals to different sub-carriers of the same time-frequency blocks. Since beams from different parts are all sent to different sub-carriers, according to the sub-carriers used by the received beams, MSs can determine from which BS the beams are coming from. And distinguish them from beams from other BSs.

The serving BS 1 may decide to send certain beams with specific time-frequency resources according to the channel related report information of the MSs. For example, when the channel related report information reported by the MS 4 includes a DoA or AoA between the MS 4 and the BS 1, the BS 1 may report the MS (reported by the MS 4). It is possible to direct beam detection signals to the target MS 4 according to DoA or AoA information between 4) and BS 1. For example, BS (1) is No. Sending the opportunistic beamforming detection signals 1C to one time-frequency resource block and directing it to the target MS 4. The opportunistic beamforming detection signals 1C are sent to two time-frequency resource blocks. In addition, BS (1) is No. 3 to No. It also sends opportunistic beamforming detection signals with 10 time-frequency resources. The present specification is No. 1 to No. Set 10 time-frequency resources as an example for illustration, and it will be appreciated that in practical application situations, the index of time-frequency resources may vary. It is not limited to the ten time-frequency resource blocks described above and may include multiple time-frequency resource blocks.

In step S106, the detection command information sent from BS 1 to BS 2 and BS 3 is No. Send opportunistic beamforming detection signals 2B to one time-frequency resource block; Instructing coordinating BS 2 to send the opportunistic beamforming detection signals 2A to the two time-frequency resource block, Send the opportunistic beamforming detection signals 3A to one time-frequency resource block. If it comprises instructing BS 3 to send the opportunistic beamforming detection signals 3C to the two time-frequency resource block, then in step S107, BS 1 indicates No. Send the opportunistic beamforming detection signals 1C to one time-frequency resource block; Send opportunistic beamforming detection signals 1C to two time-frequency resource blocks; According to the detection command information from the BS 1, the BS 2 is no. Send the opportunistic beamforming detection signals 2B to one time-frequency resource block, Send opportunistic beamforming detection signals 2A to two time-frequency resource blocks; Correspondingly, in step S107, in accordance with the detection instruction information from BS 1, BS 3 is assigned to No. Send the opportunistic beamforming detection signals 3A to one time-frequency resource block, The opportunistic beamforming detection signals 3C are sent to two time-frequency resource blocks.

In step S107, BS 2 and BS 3 are No3 to No. 3. It is possible to send opportunistic beamforming detection signals in 10 time frequency resource blocks.

Subsequently, in step S108, the BS 1 is No. 1. 1 to No. Further instructs the MS 4 to measure the opportunistic beamforming detection signals from each BS in all or part of the 10 time-frequency resource blocks.

Alternatively, in step S108, BS 1 reports to MS 4 the manner and condition of reporting indication information of the recommended cooperative communication modes generated according to the measurement of the beamforming detection signals to BS 1. Further instructions.

Then, in step 109, according to the indication of BS 1, MS 4 measures the strength of the opportunistic beamforming detection signals on the indicated time-frequency blocks, respectively. Step 109 and step 110 are described in detail below with reference to FIG.

4A shows that MS (4) is No. 1. A schematic diagram of detecting opportunistic beamforming detection signals from multiple BSs on one time-frequency block. 4B shows that MS (4) is No. 1. A schematic diagram of detecting opportunistic beamforming detection signals from multiple BSs on two time-frequency blocks.

As shown in Fig. 4A, No. On one time-frequency block, the MS 4 may detect beam signals from three BSs. Because different BSs use different sub-carriers to send beam signals, the MS 4 can each distinguish which BS its received signals are from.

In this embodiment, the MS 4 measures the opportunistic beamforming detection signals from the serving BS 1 and the coordinating BSs 2, 3, respectively. For example, the signal strength from the serving BS 1 detected by the MS 4 is equal to or greater than a first predefined threshold, for example -85 dBm, for example the serving detected by the MS. The signal strength from BS 1 is -80 dBm and the signal strength from at least one adjusting BS is greater than or equal to a second predefined threshold, for example -90 dBm, for example a second predefined When the signal strengths from the coordinating BSs 2, 3 detected by the MS 4 are -84 dBm and -85 dBm, above the set threshold, the MS 4, according to the indication of the BS 1, Can take this cooperative communication mode, where BS 1, BS 2, and BS 3 are cooperative communication modes recommended by the MSs, in which case they correspond to or correspond to the respective beams. No. One time-frequency resource block may be taken to provide data services to the serving BS for MSs (for convenience of illustration, hereinafter referred to as the first recommended cooperative communication mode).

The signal strengths from the serving BS 1 detected by the MS 4 with a plurality of time-frequency resources are greater than or equal to the first predefined threshold, and the at least one signal strength from the coordinating BSs is greater than or equal to the second preset. When the prescribed threshold is above, according to the BS 1's indication, the MS 4 takes as the recommended cooperative communication mode to report to the serving BS 1 all the plurality of cooperative communication modes that satisfy the above conditions. Can be. Also, according to the BS 1's indication, the MS 4 may select the mode with the greatest gain as the recommended cooperative communication mode.

In step S110, according to the report command information of the BS 1, the MS 4 reports indication information indicating to the BS 1 one or more first recommended cooperative communication modes.

In another case, No. With two time-frequency resources, as shown in FIG. 4B, the signal strength from BS 1 detected by MS 4 is greater than or equal to a third threshold, eg, −60 dBm, eg, The signal strength from BS 1 detected by the MS is -55 dBm, and the signal strength from BSs 2 and 3 is less than a fourth predefined threshold, for example -100 dBm, for example. When the signal strengths from the coordinating BSs 2, 3 detected by the MS 4 are -105 dBm and -120 dBm, both of which are less than -100 dBm, respectively, according to the instruction of the BS 1, the MS ( 4) is this cooperative communication mode, in which BS 1 corresponds to this beam or a No. Recommended cooperation for BS 1, which provides data services for the MS 4 with two time-frequency resources and at least one coordinating base station suppresses interference to the MS, hereinafter referred to as the second recommended cooperative communication mode. It can take as a communication mode. In return, the second recommended cooperative communication mode is that only BS 1 provides data services for MS 4 with this beam or with a time-frequency resource corresponding to the beam and at least one coordination base station, preferably with communication. The beam sent by the BS 2 in such a way that the BS 2 with the largest interference on the MS 4 on the resource (its signal strength is -105 dBm, the largest) suppresses the interference on the MS. The direction indicates to steer with the BS 1 in a way that avoids the direction of the MS 4. In an actual system, in the case of interference suppression, the efficiency of how all coordinating BSs suppress interference to the MS is not great. Therefore, in general, where the system error rate is tolerated, the signals of the BS that most interfere with the MS need only reliably avoid the direction of the MS.

In step S110, according to the BS 1's indication, the MS 4 may report the relevant command information of the second recommended cooperative communication mode to the BS 1.

Certainly, the signal strengths from the serving BS 1 with the plurality of time-frequency resources detected by the MS 4 are above a third predefined threshold, and the signal strength from each adjusting BS is equal to the fourth. When below the predefined threshold, according to the BS 1's indication, the MS may take as the recommended cooperative communication mode to report to the serving BS 1 all the plurality of common communication modes that satisfy the above conditions. Preferably, the MS 4 selects the mode with the largest signal strength from the serving BS 1 as the recommended cooperative communication mode, for example, as the second recommended cooperative communication mode, and in step S110, Report relevant indication information of the second recommended cooperative communication mode to BS 1 in order to save link feedback bandwidth.

Certainly, the MS 4 can simultaneously report to the BS 1 the first recommended cooperative communication mode and the second recommended cooperative communication mode according to the instruction of the BS 1, or to report to the BS 1. You can choose a mode with greater gain from both modes. For example, if the system capacity obtained by applying the first recommended cooperative communication mode is larger than the system capacity obtained by applying the second recommended cooperative communication mode, the MS 4 only indicates the indication information corresponding to the first recommended cooperative communication mode. If small, the MS 4 reports only the indication information corresponding to the second recommended cooperative communication mode.

The first predefined threshold, the second predefined threshold, the third predefined threshold and the fourth predefined threshold described above are merely exemplary. Those skilled in the art can select other thresholds depending on the actual situation.

Certainly, if the MS finds on one time-frequency resource block that the detected signal strength detected from the serving BS is above the third threshold and all detected detected signal strengths from the coordinating BSs are below the fourth threshold, i.e. If only serving BS 1 provides data services for the MS and corresponds to a communication scheme in which at least one of the other coordinating BSs, for example BS 3, suppresses interference to the MS, all time-frequency in the frame Resource blocks, for example No. 1 time-frequency resource to no. After going through the 10 time-frequency resources, the MS takes this communication scheme as the recommended cooperative communication mode and the corresponding index of the time-frequency block, e.g. Report the time-frequency block to BS 1.

Therefore, in step S110, according to the report command information of BS 1, MS 4 reports communication resources and / or MIMO features corresponding to the cooperative communication mode recommended thereby to serving BS 1 by way of example. do.

For example, according to the instruction of the BS 1, the MS 4 has a BS (1), a BS (2) and a BS (3) simultaneously. A scheme corresponding to providing data services for the MS in one time-frequency resource block and / or with beams as shown in FIG. 4A corresponding to the scheme recommended by the MS 4 as shown in FIG. 4A. In addition, the MS (4) is a BS (1) No. Two time-frequency resource blocks to provide data services for the MS and the BS 2 no. In coordination with the BS 1 in a manner that suppresses interference to the MS 4 with two time-frequency resource blocks and / or with beams as shown in FIG. 4B corresponding to the manner as shown in FIG. 4B. You can report how you respond. In particular, according to the indication of the BS 1, the MS 4 has an index of a time-frequency block suitable for providing a plurality of BSs at the same time to provide data services for the MS 4, and only the serving BS has an MS 4 Provide data services and report to BS 1 that the index of the time-frequency block is 2 suitable for at least one coordinating BS to suppress interference to MS 4.

Alternatively, in step S110, according to the indication of BS 1, MS 4 may select a mode with greater gain from the two cooperative communication modes to report to BS 1. For example, the serving BS and the coordinating BSs are simultaneously Nos. The system capacity corresponding to the cooperative mode of providing data services in one time-frequency resource block is that only the serving base station provides data services and the at least one coordinating base station no. When the system 4 is larger than the system capacity corresponding to the cooperative mode of suppressing interferences to the MS 4 with a two-time frequency-frequency lower block, the MS 4 determines the first recommended cooperative communication mode and its corresponding no. Only one time-frequency resource block is reported to BS 1 and, conversely, when small, MS 4 receives the second recommended cooperative communication mode and its corresponding No. It only reports 2 time-frequency resource blocks to BS 1.

Alternatively, in step S110, the MS 4 may report each detected signal strength or capacity corresponding to the recommended cooperative communication mode recommended to the BS 1. For example, the MS 4 has a signal strength detected from the serving BS 1 of -80 dBm and signal strengths detected from the adjusting BSs 2 and 3, respectively. -84 dBm and -85 dBm on the time-frequency resource block, the signal strength detected from the serving BS 1 is -55 dBm, and the signal strengths detected from the BSs 2, 3 are no. Report to BS 1 that they are -105 dBm and -120 dBm, respectively, on the two time-frequency resource blocks.

Then, in step S111, according to the indication information of the recommended cooperative communication mode obtained from the MSs served by the serving BS 1, the serving BS 1 completely schedules and schedules at least one of the MSs. It provides a communication scheme corresponding to the recommended cooperative communication mode recommended by the MS for the MS. In particular, for example, BS 1 has two recommended communication modes recommended by MS 4, namely No. In one time-frequency resource block, a communication scheme in which BS 1, BS 2 and BS 3 provide data services for the MS 4 by coordination, and No. With 2 time-frequency resources, only BS 1 provides data services for MS 4 and the MS 2 provides indication information indicating a coordinated communication scheme that suppresses interference to MS 4. )

Alternatively, some coordinating BS, e.g., BS 2 has a service with higher priority for processing, BS 2 cannot be synchronized with BS 1, or for other reasons, If the degree of freedom of 2) is limited, the BS 1 may determine a communication scheme different from the cooperative mode recommended by the MS, for example, the serving BS 1 may be configured with the MS 4 without coordination with other BSs. Choose to provide services for the BS 1 or BS 3. Provide data services for the MS 4 by coordination with one time-frequency resource, and the BS 2 no. Scheduling coordination with BS 1 and BS 3 in a manner that suppresses interference to MS 4 with one time-frequency resource, or BS 1 may only be BS 1 for MS 4 . 2 time-frequency resource blocks to provide data services for the MS (4) and BS (3). Scheduling to coordinate with BS 1 in a manner that suppresses interference to MS 4 with two time-frequency resource blocks.

Certainly, if the indication information from the MS 4 received by the BS 1 includes only one recommended cooperative communication mode, the BS 1 is fed back by each MS served by the BS 1. And the relevant occupancy situation of coordinating BSs for scheduling. The specific scheduling scheme of BS 1 is similar to that of BS 1 and will not be described here when the indication information reported by MS 4 includes the various recommended cooperative communication modes described above.

Subsequently, in step S112, BS 1 may provide data communication services for MS 4 using specific beams with specific time-frequency resources and as a result of the scheduling. ), Which informs the scheduled MS 4 to execute the corresponding MIMO communication with specific time-frequency resources.

For example, BS 1 is No. Inform BS 2 to perform data service transmission in a direction to avoid MS 4 with one time-frequency resource, and send beamforming data and weight related information according to the direction of opportunistic beamforming detection signals sent previously. Inform BS (3) or No. Inform BS 2 to execute data service transmission in a direction to avoid MS 4 with two time-frequency resources.

BS 1 also informs MS 4 to perform the corresponding MIMO communication with specific time-frequency resources. In particular, BS 1 simultaneously receives MIMO data signals from BS 1 and BS 2, or no. No. 2 for receiving data signals from BS 1 with a time-frequency resource. Inform the MS 4 to use two antennas for one time-frequency resource.

Subsequently, in step S113, BS 1, BS 2 and BS 3 send MIMO communication with the scheduled MS 4 to specific time-frequency resources, respectively, and instructed in step S112, respectively. Along with specific beams.

In step S114, the MS 4 obtains an equivalent channel response and detects signals according to the equivalent channel response.

In another embodiment, each detection signal under the beamforming process described above may be replaced with a detection signal under precoding with any codebook in the codebook and does not affect the features of the present invention.

In other embodiments, steps S100 through S103 may be omitted. That is, the serving BS 1 sends one or more different opportunistic beamforming detection signals randomly to one or more time-frequency resources from the MSs without the need for channel related report information.

In other embodiments, steps S104 through S106 may be omitted. Each coordinating BS agrees with the serving BS in which communication resources and in which direction opportunistic beamforming detection signals will be sent in the initial period of network configuration. Therefore, step S107 may be replaced by step 107 ', where in step 107' the serving BS and the coordinating BSs respectively send agreed beam detection signals to specific communication resources in accordance with the agreement.

In other embodiments, step S108 may be omitted. The MS 4 and serving BSs agreed during which period of network configuration, at which frame (s) of which time slot (s) the MS will detect opportunistic beamforming detection signals. Therefore, step S109 can be replaced with step S109 '. In step S109 ', the MS 4 detects the opportunistic beamforming detection signals received in the agreed one or more time slots of the one or more frames.

In addition, the MS and the serving BS can agree on how and under what conditions the MS will report indication information corresponding to the cooperative communication mode recommended for the serving BS. Therefore, step S110 may be replaced with step S110 ', i.e., the MS does not need to obtain report indication information from the serving BS in real time, and the cooperative communication mode recommended to the serving BS in a specific manner when the conditions are satisfied. The instruction information corresponding to the can be reported.

In another embodiment, step S110 may be omitted. That is, in some certain scenarios, the MS agrees with the serving BS not to report indication information. These scenarios are when the signal detected by the MS from the serving BS is below the fifth predefined threshold, or the beam signals detected by the MS from the serving BS and the beam signals detected by the MS from the steering BSs are multi- When not suitable for BS cooperation and not in an interference-suppression communication scheme, and the like. Therefore, in this frame, there is no BS to service the MS that did not report indication information. However, the BS will provide service for this user in the next frames.

In another embodiment, the BS may send different opportunistic beamforming detection signals over different antennas with the same time-frequency resource to obtain spatial diversity or gain.

Also, there is no strict order between step S106 and step S108. BS 1 may execute step S106 and step S108 simultaneously, or execute step S106 first and then execute step S108, or execute step S108 first and then step S106. ) Can be executed.

FIG. 5 shows a first providing apparatus 10, coordinating BSs 2, 3, to a serving BS 1 in order to perform MIMO-based multi-BS cooperative communication in a wireless communication network according to an embodiment of the invention. Is a block diagram of the first aiding device 20 and the second aiding device 30 to the MS 4.

The first providing device 10 is located in the BS 1 shown in FIG. The first providing device 10 includes the report obtaining means 100, the determining means 101, the first signal transmitting means 102, the command generating means 103, the command transmitting means 104, and the instruction information obtaining means 105. ) And second providing means 106.

The first aiding apparatus 20 comprises a first command acquiring means 200 and a second signal transmitting means 201.

The second aiding device 30 includes a second command obtaining means 301, a signal obtaining means 302, a measuring means 303, an indication information generating means 304, and an indication information reporting means 305.

2 and 1, a block diagram of the systematic method of the present invention has been described in detail. The case of communication between BS 1, BS 2, BS 3, and MS 4, MS 5 is taken as an example for describing an embodiment of the present invention as follows.

First, MS 4 determines BS 1 as its serving BS. When turned on to access the network, the MS 4 registers the relevant information with the BS 1, so that the BS 1 becomes the serving BS of the MS 4, or in other cases, the MS is between cells. When executing the handover, the MS 4 moves from its home cell to the neighbor cell and sets up communication with the target BS 1 in the neighbor cell. Accordingly, BS 1 is the serving BS of MS 4. Likewise, MS 5 determines BS 1 as its serving BS. Although only the MS 4 and the MS 5 are shown for convenience of illustration as only two MSs served by the BS 1, in an actual network configuration, the BS may serve one or more MSs. Certainly, the present invention can be applied to the BS 1 serving multiple MSs.

BS 1 then instructs MS 4 and MS 5 served by BS 1 to measure and report channel related information, respectively. In particular, BS 1 allocates uplink control channels for MS 4 and MS 5 and MS 4 and MS 5 report the measurement results of their channel related information to this control channel. Set the conditions for reporting channel related report information.

The MSs 4 and 5 then measure channel related information, respectively, to generate channel related report information. In particular, the channel related report information may include channel quality related information, for example, RSSI (received signal strength indicator), CINR (carrier interference to noise ratio), or CQI (channel quality indicator), and also MS Location information, for example, DoA (reach direction) or AoA (reach angle) of the MS.

Since there is no need to process and demodulate the received sampled signals, estimating RSSI is easier and the computation is not too complex. However, received signals on the one hand also include noise, interference and other channel loss, so that the received signals are strong does not mean that the channel and signal quality are good, but only that there are only strong signals in the channel.

CINR (or SNR or SINR) provides information on how strong the desired signals are relative to interference (or noise or interference and noise). Most wireless communication systems are limited to interference, so CIR and CINR are generally more applicable. Compared to RSSI, these measurement results provide a more accurate and reliable estimate, but the cost is more complex calculations and extra delays. The CINR can be estimated by estimating signal power and interference power, respectively, and then obtaining the ratio of the two values. This channel parameter can be used to calculate the signal power.

It is known to those skilled in the art how MSs make measurements of RSSI, CINR, CQI and DoA. Accordingly, the present invention will not be described here.

The MSs 4, 5 can measure channel related information between them and the serving BS, i. E. BS 1, and not only the channel related report information but also these and other BSs, e.g. BSs 2, 3 Channel-related information can be measured.

After performing the operation described above, the reporting means 300 of the MSs 4, 5 are notified by the BS 1 for each channel related report information for the BS 1, or for each BS 1. Provides channel related report information that satisfies the set channel related report information conditions.

In another embodiment, MSs 4 and 5 have already obtained command information from BS 1 in advance. That is, the MSs 4 and 5 already know the control channel and the conditions under which the channel related report information should be reported to the BS 1. Therefore, the reporting means 300 periodically report their channel related report information to the BS 1 without having to rely on the previous operations of the MSs 4 and 5 and the BS 1.

Then, the requesting means for sending to the first providing apparatus 10 (not shown) according to the report results of the channel related report information of the one or more MSs served by the BS 1 detects the detection signal according to the specific MIMO features. Sends a request to one or more neighboring BSs. In this embodiment, these detection signals according to certain MIMO features are considered as opportunistic beamforming detection signals to use as an example to illustrate the present invention.

In particular, according to the obtained channel related report information of the plurality of MSs, including the channel related information obtained from the MS 4 and the MS 5 by the report obtaining means 100, the BS 1 cooperates with the multi-BS. Determine which MS needs to be served in the MIMO scheme and which BSs to set up the cooperative MIMO scheme. Once the multi-BS cooperative MIMO scheme is selected, the send request means must send an opportunistic beamforming detection signal send request to certain neighboring BSs. In this embodiment, the serving BS 1 is served by the MS 4 in such a way that the collaborative MIMO is set up with the BS 2 and BS 3 while the MS 5 is serviced in a non-cooperative MIMO manner. Decide to be. In this embodiment, the serving BS 1 simultaneously selects the serving MS 4 and the MS 5 with the same time-frequency resources. Accordingly, the conventional single-BS multi-user MIMO scheme has been established between BS 1, MS 4, and MS 5. The principle of operation of the multi-BS cooperative MIMO of the present invention will be described next using the MS 4 as an example. MS 5 will not be described.

Subsequently, request deciding means (not shown) to the first aiding apparatus 20 of each described requested BS are presented together with the BS 1 initiated by the BS 1 according to information such as resource occupancy status. It is determined whether to accept the request for sending the beamforming detection signal. In this embodiment, the request determination means to BS 2 and BS 3 send decision information to BS 1 to determine to send opportunistic beamforming detection signals in cooperation with BS 1.

When BS 1 obtains a request to accept beamforming detection signal transmission from one or more neighboring BSs, for example BS 2 and BS 3, command generating means 103 is opportunistic beamforming. Instructs coordinating BS 2 and BS 3 to send detection signals.

Preferably, the instruction generating means 103 further instructs the coordinating BSs 2 and 3 which specific beams should be sent with specific time-frequency resources in order to point out or not point out specific MSs or to send random beams. . Therefore, coordinating BSs 2, 3 obtain indication information from BS 1 with which time-frequency resources in which direction the beams will be sent. For example, BS 1 is No. Instruct BSs 2 and 3 to send opportunistic beamforming detection signals 2B and 3A in one time-frequency block, respectively, hoping to point or not point to MS 4. Instruct BSs 2 and 3 to send opportunistic beamforming detection signals 2A and 3C in two time-frequency blocks, respectively.

The command transmitting means 104 then sends the instructions described above to the BS 2 and the BS 3.

The first signal transmitting means 102 of the BS 1 and the second signal transmitting means 201 of the coordinating BSs 2 and 3 simultaneously transmit opportunistic beamforming detection signals to a specific time-frequency block.

The transmission process of the beam signals by the BSs 1, 2, 3 will be described in detail as follows. 3 describes an example where a plurality of BSs send a plurality of opportunistic beamforming detection signals equally. The basic idea of so-called opportunistic beamforming is almost certainly that the throughput of the system can be maximized by allocating channels preferably to users who can complete successive transmissions. For reflective spatial channels, the opportunistic beamforming scheme can point out users with the largest SINR, whereas in the case of sufficient scattering, the opportunistic mechanism will assign channels to the users with the largest instantaneous capacity. will be.

In this embodiment, each cell is divided into three sectors as shown in FIG. Each sector is 120 degrees. Here BS 1 is located in the center of the cell, which corresponds to a sector having 120 degrees in the cell. The BS 1 can send beams in six kinds of directions. The six beams were indicated as 1A-1F clockwise, respectively. Not all reference signs of the beams are indicated in view of the paper space limitations. It will be appreciated that the sector may correspond to eight beams or some other beams and may be configured by the BS serving this sector. Thus, as an example, BS 2 sends beams in six types of directions, clockwise arranged, indicated by 2A to 2F in the sector served by BS 2. The BS 3 also sends beams in six directions, arranged in a clockwise direction, indicated by 3A to 3F in the sector served by the BS 3.

In this embodiment, all sectors are divided into parts A, B and C as three parts, respectively. Each part contains several non-neighboring sectors. Sectors served by BS 1 are located in part A, sectors served by BS 2 are located in part B, and sectors served by BS 3 are part C My location is BSs belonging to different parts may send beam detection signals to different sub-carriers of the same time-frequency blocks. Since beams from different parts are all sent to different sub-carriers, according to the sub-carriers used by the received beams, MSs can determine from which BS the beams are coming from. And distinguish them from beams from other BSs.

In particular, the determining means 101 of the serving BS 1 may decide to send certain beams with specific time-frequency resources according to the channel related report information of the MSs. For example, when the channel related report information reported by the MS 4 includes DoA or AoA between the MS 4 and the BS 1, the determining means 101 determines the MS reported by the MS 4. It is possible to direct beam detection signals to the target MS 4 according to DoA or AoA information between the (4) and the BS (1). For example, the determining means 101 is a No. Sending the opportunistic beamforming detection signals 1C to one time-frequency resource block and directing it to the target MS 4. Send and determine the opportunistic beamforming detection signals 1C with two time-frequency resource blocks. In addition, BS (1) is No. 3 to No. It also sends opportunistic beamforming detection signals with 10 time-frequency resources. The present specification is No. 1 to No. Set 10 time-frequency resources as an example for illustration, and it will be appreciated that in practical application situations, the index of time-frequency resources may vary. It is not limited to the ten time-frequency resource blocks described above and may include multiple time-frequency resource blocks.

The detection command information sent from the command transmission means 104 to the BS 2 and the BS 3 is No. 2. Send opportunistic beamforming detection signals 2B to one time-frequency resource block; Instructing coordinating BS 2 to send the opportunistic beamforming detection signals 2A to the two time-frequency resource block, Send the opportunistic beamforming detection signals 3A to one time-frequency resource block. If it comprises instructing BS 3 to send the opportunistic beamforming detection signals 3C to the two time-frequency resource block, the first signal transmitting means 102 is No. 1. Send the opportunistic beamforming detection signals 1C to one time-frequency resource block; Send opportunistic beamforming detection signals 1C to two time-frequency resource blocks; In accordance with the detection command information from the command transmitting means 104, the second signal transmitting means 201 is no. Send the opportunistic beamforming detection signals 2B to one time-frequency resource block, Send opportunistic beamforming detection signals 2A to two time-frequency resource blocks; Correspondingly, in accordance with the detection command information from the command transmitting means 104, the second signal transmitting means 201 is no. Send the opportunistic beamforming detection signals 3A to one time-frequency resource block, The opportunistic beamforming detection signals 3C are sent to two time-frequency resource blocks.

In addition, the second signal transmission means of the BS 2 and the BS 3 also has a no. 3 to No. It is possible to send opportunistic beamforming detection signals in 10 time frequency resource blocks.

Subsequently, the command transmitting means 104 of the BS 1 also shows a No. 1 to No. The MS 4 can be instructed to measure opportunistic beamforming detection signals from each BS in all or part of the 10 time-frequency resource blocks.

Alternatively, the command transmitting means 104 also instructs the MS 4 how and conditions to report to BS 1 the indication information of the recommended cooperative communication modes generated according to the measurement of the beamforming detection signals. In other words, the command transmitting means 104 sends an instruction to the second command obtaining means 301.

Then, according to the instruction from the command transmitting means 104 obtained by the second command obtaining means 301, the signal obtaining means 302 and the measuring means 303 of the MS 4 are on the indicated time-frequency blocks. Measure the strength of the opportunistic beamforming detection signals, respectively. An operation performed by the signal acquiring means 302 and the measuring means 303 will be described in detail below with reference to FIG.

In accordance with the instruction obtained by the second command obtaining means 301, the measuring means 303 is No. 2. 1 and No. Opportunity beamforming detection signals may be detected on two time-frequency blocks or other time-frequency blocks.

4A shows that MS (4) is No. 1. A schematic diagram of detecting opportunistic beamforming detection signals from multiple BSs on one time-frequency block. 4B shows that MS (4) is No. 1. A schematic diagram of detecting opportunistic beamforming detection signals from multiple BSs on two time-frequency blocks.

As shown in Fig. 4A, No. On one time-frequency block, the measuring means 303 of the MS 4 can detect beam signals from three BSs. Since different BSs use different sub-carriers to send beam signals, the measuring means 303 can each distinguish which BS its received signals are from.

In this embodiment, the measuring means 303 measures the opportunistic beamforming detection signals from the serving BS 1 and the coordinating BSs 2, 3, respectively. For example, the signal strength from the serving BS 1 detected by the measuring means 303 is equal to or greater than a first predefined threshold, for example -85 dBm, for example the measuring means 303. The signal strength from the serving BS 1 detected by is -80 dBm and the signal strength from the at least one adjusting BS is equal to or greater than a second predefined threshold, for example -90 dBm. Second command obtaining means 301 when the signal strengths from the coordinating BSs 2, 3 detected by the measuring means 303 are -84 dBm and -85 dBm, above the second predefined threshold; In accordance with the instruction obtained by e), the indication information generating means 304 may take this cooperative communication mode, in which the BS 1, BS 2, and BS 3 are sent to the MSs in order to generate the indication information. Cooperative communication modes recommended by the present invention, wherein in this case the respective beams or corresponding Nos. One way may be to provide data services for MSs in one time-frequency resource block (for convenience of example, hereinafter referred to as the first recommended cooperative communication mode). And indication information reporting means 305 provide indication information for the serving BS 1.

The signal strengths from the serving BS 1 detected by the measuring means 303 with a plurality of time-frequency resources are above a first predefined threshold and at least one signal strength from the coordinating BSs is second. When the predefined threshold value is above, in accordance with the instruction obtained by the second instruction obtaining means 301, the instruction information generating means 304 displays instruction information reporting means 305 for all the plurality of cooperative communication modes that satisfy the above conditions. ) Can be taken as the recommended cooperative communication mode for reporting to the serving BS 1. Further, in accordance with the instruction obtained by the second command obtaining means 301, the instruction information generating means 304 selects the mode having the greatest gain as the recommended cooperative communication mode, for example, the first recommended cooperative communication mode. You can choose. And the indication information reporting means 305 reports to the BS 1 indication information indicating one or more first recommended cooperative communication modes.

In another case, No. With two time-frequency resources, as shown in FIG. 4B, the signal strength from the BS 1 detected by the measuring means 303 has a third threshold, for example, -60 dBm or more, for example The signal strength from the BS 1 detected by the measuring means 303 is -55 dBm, and the signal strength from the adjusting BSs 2, 3 is a fourth predefined threshold, e. Obtaining a second command when the signal strength from coordinating BSs 2, 3 detected by measuring means 303 is less than -100 dBm, respectively -105 dBm and -120 dBm, respectively, less than 100 dBm According to the instruction obtained by the means 301, the instruction information generating means 304 is this cooperative communication mode, in which BS 1 corresponds to this beam or a No. corresponding to this beam. Recommended cooperation for BS 1, which provides data services for the MS 4 with two time-frequency resources and at least one coordinating base station suppresses interference to the MS, hereinafter referred to as the second recommended cooperative communication mode. It can take as a communication mode. In return, the second recommended cooperative communication mode is that only the BS 1 provides data services for the MS 4 with this beam or with a time-frequency resource corresponding to the beam and at least one coordination base station, preferably a communication resource. The beam direction sent by the BS 2 in such a way that the BS 2 with the largest interference on the MS 4 (its signal strength is -105 dBm, the largest) suppresses the interference on the MS. Instructs the BS 1 to steer in a manner that avoids the direction of the MS 4. In a practical system, in the case of interference suppression, the efficiency of how all coordinating BSs suppress interference to the MS is not great. Therefore, in general, when the system error rate is tolerated, the signal of the BS that most interferes with the MS need only reliably avoid the direction of the MS.

According to the instructions obtained by the second command obtaining means 301, the indication information reporting means 305 can report the relevant command information of the second recommended cooperative communication mode to the BS 1.

Certainly, the signal strengths from the serving BS 1 with a plurality of time-frequency resources detected by the measuring means 303 are above a third predefined threshold, and the signal strength from each adjusting BS is fourth. According to the instruction obtained by the second instruction obtaining means 301 when less than a predefined threshold of, the instruction information generating means 304 sends all the plurality of cooperative communication modes to the serving BS 1 that satisfy the above conditions. Can be taken as the recommended cooperative communication mode for reporting. Preferably, the indication information generating means 304 selects the mode having the largest signal strength from the serving BS 1 as the recommended cooperative communication mode, for example, as the second recommended cooperative communication mode, and the indication information reporting means. 305 reports the relevant indication information of the second recommended cooperative communication mode to BS 1 in order to save uplink feedback bandwidth.

Certainly, the indication information reporting means 305 can simultaneously report to the BS 1 the first recommended cooperative communication mode and the second recommended cooperative communication mode according to the instruction obtained by the second command obtaining means 301, Alternatively, one may select a mode with greater gain from both modes to report to BS 1. For example, if the system capacity obtained by applying the first recommended cooperative communication mode is larger than the system capacity obtained by applying the second recommended cooperative communication mode, the indication information reporting means 305 corresponds to the first recommended cooperative communication mode. Report only the indication information, and if small, the indication information reporting means 305 reports only the indication information corresponding to the second recommended cooperative communication mode.

Note that the first predefined threshold, the second predefined threshold, the third predefined threshold and the fourth predefined threshold described above are exemplary only. Those skilled in the art can select other thresholds depending on the actual situation.

Certainly, the measuring means 303 of the MS is on one time-frequency resource block, the detection signal strength detected from the serving BS is above the third threshold and all the detected detection signal strengths from the coordinating BSs are the fourth threshold. If found to be less than, i.e., only serving BS 1 provides data services for the MS and at least one of the other coordinating BSs, e.g. BS 3, corresponds to a communication scheme that suppresses interference to the MS, All time-frequency resource blocks in the frame, e.g. 1 time-frequency resource to no. After passing 10 time-frequency resources, the MS's indication information generating means 304 takes this communication scheme as the recommended cooperative communication mode and the indication information reporting means 305 selects the corresponding index of the time-frequency block, e. No. Report the time-frequency block to BS 1.

According to the report command information obtained by the second command obtaining means 301, the indication information reporting means 305 thereby sends the communication resources and / or MIMO features corresponding to the recommended cooperative communication mode to the serving BS 1. Report.

For example, in accordance with the report command information obtained by the second command obtaining means 301, the indication information reporting means 305 is a BS (1), BS (2) and BS (3) at the same time. A scheme corresponding to providing data services for the MS in one time-frequency resource block and / or with beams as shown in FIG. 4A corresponding to the scheme recommended by the MS 4 as shown in FIG. 4A. And BS (1) is no. Two time-frequency resource blocks to provide data services for the MS and the BS 2 no. In coordination with the BS 1 in a manner that suppresses interference to the MS 4 with two time-frequency resource blocks and / or with beams as shown in FIG. 4B corresponding to the manner as shown in FIG. 4B. You can also report the corresponding method. In particular, according to the indication of the BS 1, the indication information reporting means 305 has an index of a time-frequency block suitable for providing a plurality of BSs at the same time to provide data services for the MS 4, and only the serving BS has an index. Report to BS 1 that the index of a time-frequency block suitable for providing data services for MS 4 and at least one coordinating BS to suppress interferences to MS 4 is two.

Alternatively, in accordance with the indication of the BS 1, the indication information reporting means 305 may select a mode with a greater gain from the two cooperative communication modes to report to the BS 1. For example, the serving BS and the coordinating BSs are simultaneously Nos. The system capacity corresponding to the cooperative mode of providing data services in one time-frequency resource block is that only the serving base station provides data services and the at least one coordinating base station no. When greater than the system capacity corresponding to a cooperative mode that suppresses interferences to the MS 4 with a two-time-frequency resource block, the indication information reporting means 305 is adapted to the first recommended cooperative communication mode and its corresponding No. When only one time-frequency resource block is reported to the BS 1, and conversely small, the indication information reporting means 305 causes the second recommended cooperative communication mode and its corresponding no. It only reports 2 time-frequency resource blocks to BS 1.

Alternatively, the indication information reporting means 305 may report each detected signal strength or capacity corresponding to the recommended cooperative communication mode recommended to BS 1. For example, MS 4 has a signal strength detected from serving BS 1 of -80 dBm and signal strengths detected from coordinating BSs 2 and 4, respectively. -84 dBm and -85 dBm on one time-frequency resource block, the signal strength detected from the serving BS 1 is -55 dBm, and the signal strengths detected from the BSs 2, 3 are no. Report to BS 1 that they are -105 dBm and -120 dBm, respectively, on the two time-frequency resource blocks.

Then, according to the indication information of the cooperative communication mode recommended from the MSs served by the serving BS 1 obtained by the indication information obtaining means 105, the second providing means 106 completes at least one of the MSs. Provide a communication scheme corresponding to the recommended cooperative communication mode recommended by the MS for the scheduled MS. In particular, for example, the indication information acquiring means 105 may include two recommended communication modes recommended by the MS 4, namely No. In one time-frequency resource block, a communication scheme in which BS 1, BS 2 and BS 3 provide data services for the MS 4 by coordination, and No. With 2 time-frequency resources, only BS 1 provides data services for MS 4 and the MS 2 provides indication information indicating a coordinated communication scheme that suppresses interference to MS 4. )

Alternatively, some coordinating BS, e.g., BS 2 has a service with higher priority for processing, BS 2 cannot be synchronized with BS 1, or for other reasons, If the degree of freedom of 2) is limited, the second providing means 106 may determine a communication scheme that is different from the cooperative mode recommended by the MS, for example, the serving BS 1 may not be able to coordinate with other BSs. (4) choose to provide services or BS (1) and BS (3) is no. Provide data services for the MS 4 by coordination with one time-frequency resource, and the BS 2 no. Scheduling coordination with BS 1 and BS 3 in a manner that suppresses interference to MS 4 with one time-frequency resource, or BS 1 may only be BS 1 for MS 4 . 2 time-frequency resource blocks to provide data services for the MS (4) and BS (3). Scheduling to coordinate with BS 1 in a manner that suppresses interference to MS 4 with two time-frequency resource blocks.

Certainly, if the indication information from the MS 4 received by the indication information obtaining means 105 includes only one recommended cooperative communication mode, the BS 1 is determined by each MS served by the BS 1. Careful consideration should be given to the relative occupancy situation of coordinating BSs for scheduling indication and feedback information. The specific scheduling scheme of the BS 1 is similar to the scheduling scheme of the BS 1 when the indication information reported by the MS 4 to the BS 1 includes the various recommended cooperative communication modes described above. Will not describe.

Subsequently, BS 1 informs BSs 2 and 3 to provide data communication services for MS 4 using specific beams with specific time-frequency resources and as a result of the scheduling, Inform the scheduled MS 4 to execute the corresponding MIMO communication with frequency resources.

For example, BS 1 is No. Inform BS 2 to perform data service transmission in a direction to avoid MS 4 with one time-frequency resource, and send beamforming data and weight related information according to the direction of opportunistic beamforming detection signals sent previously. Inform BS (3) or No. Inform BS 2 to execute data service transmission in a direction to avoid MS 4 with two time-frequency resources.

BS 1 also informs MS 4 to perform the corresponding MIMO communication with specific time-frequency resources. In particular, BS 1 simultaneously receives MIMO data signals from BS 1 and BS 2, or no. No. 2 for receiving data signals from BS 1 with a time-frequency resource. Inform the MS 4 to use two antennas for the two time-frequency resources.

Subsequently, the BS 1, BS 2 and BS 3 perform MIMO communication with the scheduled MS 4 with specific time-frequency resources and with specific beams according to the scheduling result of the first providing apparatus 10, respectively. Run with

The MS 4 then obtains an equivalent channel response and detects signals according to the equivalent channel response.

In another embodiment, each detection signal under the beamforming process described above may be replaced with a detection signal under precoding with any codebook in the codebook and does not affect the features of the present invention.

In another embodiment, the report obtaining means 100 and the determining means 101 may be omitted. That is, the first signal transmitting means 102 randomly sends one or more different opportunistic beamforming detection signals from the MSs to one or more time-frequency resources without the need for channel related report information.

In another embodiment, the command generating means 103, the command transmitting means 104, the first command obtaining means 200, and the second command obtaining means 301 may be omitted. Each coordinating BS agrees with the serving BS in which communication resources and in which direction opportunistic beamforming detection signals will be sent in the initial period of network configuration. Therefore, the first signal transmitting means 102 and the second signal transmitting means 201 each send the agreed beam detection signals to specific communication resources periodically in accordance with the agreement.

In addition, the MS 4 and the serving BSs agreed that during the duration of the network configuration, the MS will detect opportunistic beamforming detection signals in which frame (s) of which time slot (s). Therefore, the second command obtaining means 301 can be omitted. The signal obtaining means 302 detects the opportunistic beamforming detection signals received in the agreed one or more time slots of the one or more frames.

In addition, the MS and the serving BS can agree on the manner and condition to report the indication information corresponding to the cooperative communication mode recommended to the serving BS for the duration of the network configuration. Therefore, the indication information reporting means 305 can report the indication information corresponding to the cooperative communication mode recommended to the serving BS when the conditions are satisfied.

In another embodiment, the indication information reporting means 305 may be omitted. That is, in some certain scenarios, the MS agrees with the serving BS not to report indication information. These scenarios include multi-BS where the signal detected by the MS from the serving BS is below the fifth predefined threshold, or the beam signals detected by the MS from the serving BS and the beam signals detected by the MS from the coordinating BSs. When not suitable for cooperation and not in an interference-suppressive communication scheme, but not limited to these. Therefore, in this frame, there is no BS to service the MS that did not report indication information. However, the BS will provide service for this user in the next frames.

In another embodiment, the BS may send different opportunistic beamforming detection signals over different antennas with the same time-frequency resource to obtain spatial diversity or gain.

Embodiments of the invention have been described above. However, the present invention is not limited to specific systems, equipment or specific protocols. Those skilled in the art can make various changes or modifications within the scope of the appended claims.

1, 2, 3: base station 4, 5: mobile station
10: first providing device 20: first aiding device
30: second aiding device 100: report acquisition means
101: means of decision
102: first signal transmitting means 103: command generating means
104: command transmission means
105: instruction information obtaining means 106: second providing means
301: second command obtaining means 302: signal obtaining means
303: measuring means
304: instruction information generating means
305: indication information reporting means

Claims (48)

A method for providing a communication scheme to one or more mobile stations served by a serving base station at a serving base station in a MIMO-based wireless communication network:
a. Sending one or more first detection signals in accordance with respective MIMO features to the one or more mobile stations, respectively, with one or more communication resources;
b. Obtaining indication information used from the one or more mobile stations for indicating information related to the communication resources and / or MIMO features corresponding to recommended cooperative communication modes recommended by the one or more mobile stations; And
c. Scheduling at least one mobile station of the one or more mobile stations according to the indication information and providing a MIMO communication scheme for the at least one scheduled mobile station to a serving base station in a MIMO-based wireless communication network. Providing a communication scheme to one or more mobile stations served by the. The method of claim 1,
The method is carried out before step (b):
i. The one or more coordination of respective detection command information used to instruct one or more coordination base stations to send one or more second detection signals in accordance with respective MIMO features to the one or more mobile stations as the one or more communication resources. Sending to the one or more mobile stations served by the serving base station at the serving base station of the MIMO-based wireless communication network. The method of claim 2,
Before step (a):
Obtaining channel related report information from the one or more mobile stations; And
Determining a MIMO features corresponding to the communication resources and / or the one or more first detection signals in accordance with the channel related report information. A serving base station at a serving base station of a MIMO-based wireless communication network. Providing a method of communication to one or more mobile stations served by a. The method of claim 3, wherein
Before step (i):
Determining MIMO features corresponding to the communication resources and / or the one or more first detection signals, and generating one or more detection command information in accordance with the channel related report information, respectively; One or more servings served by a serving base station in a serving base station of a MIMO-based wireless communication network, the detection command information comprising respective MIMO features corresponding to the respective communication resources and / or the respective second detection signals. A method of providing a communication scheme to mobile stations. The method according to claim 3 or 4,
The channel related report information of the one or more mobile stations reported by the one or more mobile stations includes a channel quality indication and / or a carrier to noise ratio and / or a received signal strength indication and / or location information of the one or more mobile stations. And providing a communication scheme to one or more mobile stations served by the serving base station at the serving base station of the MIMO-based wireless communication network. The method according to any one of claims 2 to 5,
Before step (b):
Measure to the one or more mobile stations to inform the one or more mobile stations to measure one or more detection signals with respective MIMO features sent by the one or more coordination base stations and the serving base station according to the one or more communication resources. Sending command information; And
Sending report command information to the one or more mobile stations to indicate the scheme and condition to the one or more mobile stations for reporting the indication information to the serving base station. Providing a communication scheme to one or more mobile stations served by the serving base station at the serving base station of the apparatus. The method according to any one of claims 2 to 6,
When the one or more recommended cooperative communication modes apply that at least one of the serving base station and the coordinating base stations simultaneously provide data services for the at least one scheduled mobile station, step (c) includes:
-Providing, according to the indication information, cooperative communication modes with communication resources and MIMO features corresponding to the one or more recommended cooperative communication modes, for the scheduled mobile stations. A method of providing a communication scheme to one or more mobile stations served by a serving base station at a serving base station of a wireless communication network. The method according to any one of claims 2 to 6,
When the one or more recommended cooperative communication modes apply that only the serving base station provides data services for the at least one scheduled mobile station and at least one coordinating base station suppresses interference to the scheduled mobile stations, Step c is:
-Providing, according to the indication information, an interference suppression communication scheme with communication resources and MIMO features corresponding to the recommended cooperative communication modes for the at least one scheduled mobile station. -A method of providing a communication scheme to one or more mobile stations served by a serving base station at a serving base station of a based wireless communication network. The method according to any one of claims 1 to 8,
The MIMO features include beamforming processing and / or codeword-weighting processing, providing a communication scheme to one or more mobile stations served by a serving base station at a serving base station of a MIMO-based wireless communication network. The method according to any one of claims 1 to 9,
Wherein the communication resources comprise a time resource and / or a frequency resource and / or a coding method. A method of providing a communication scheme to one or more mobile stations served by a serving base station at a serving base station of a MIMO-based wireless communication network. A method of assisting a serving base station to provide a communication scheme to a mobile station served by coordination by a coordination base station in a MIMO-based wireless communication network:
I. Sending one or more second detection signals in accordance with MIMO features to the one or more mobile stations as one or more communication resources. The method of claim 11,
Before step (I):
Obtain detection command information from the serving base station used to instruct the coordinating base stations to send one or more second detection signals according to respective MIMO features to the one or more mobile stations with corresponding one or more communication resources. The method further comprises the step of serving base station assistance. The method according to claim 11 or 12,
And the detection signals according to MIMO features comprise detection signals under beamforming processing and / or codeword-weighting processing. The method according to any one of claims 11 to 13,
And said communication resources comprise a time resource and / or a frequency resource and / or a coding method. A method for assisting a serving base station to provide a communication scheme to a mobile station at a mobile station in a MIMO-based wireless communication network, the method comprising:
A. obtaining at least one detection signals in accordance with MIMO features sent to one or more communication resources from one or more base stations including the serving base station;
B. measuring signal strength of at least one of the detection signals according to MIMO features sent by one or more base stations to at least one of the one or more communication resources; And
C. one or more indication information used for indicating information related to the communication resources and / or MIMO features corresponding to one or more recommended cooperative communication modes recommended by the mobile station, according to the measured signal strength. And generating the above indication information. The method of claim 15,
Before step (C):
D. reporting the indication information to the serving base station. The method according to claim 15 or 16,
The signal strength of the first detection signal sent by the serving base station to a communication resource, detected by the mobile station, is above a first predefined threshold and is detected by the mobile station at least one of the corresponding resources. When the signal strength of the second detection signal sent by the coordination base station of is greater than or equal to a second predefined threshold, the one or more recommended cooperative communication modes indicate that the serving base station and the at least one coordination base station are for the mobile station. And providing the data services simultaneously and wherein the indication information includes the corresponding communication resources. The method according to claim 15 or 16,
The signal strength of the first detection signal sent by the serving base station to a communication resource, detected by the mobile station, is above a third predefined threshold and is sent by each coordinating base station to corresponding resources; When the signal strength of the second detection signal is below a fourth predefined threshold, the one or more recommended cooperative communication modes indicate that only the serving base station provides data services for the mobile station and that at least one coordinating base station is selected by the mobile stations. Applying suppression for interference and wherein the indication information comprises the corresponding communication resources. The method of claim 17 or 18,
The instruction information is:
-Further comprising a signal strength of the first detection signal and / or the second detection signal on the corresponding communication resources. 20. The method according to any one of claims 15 to 19,
Before step (A):
Receiving measurement command information from the serving base station to instruct the mobile station one or more communication resources used to measure detection signals;
The step (A) further comprises obtaining a plurality of detection signals in accordance with MIMO features sent from the plurality of base stations to the one or more communication resources in accordance with the one or more communication resources indicated by the measurement command information. Including,
The method is carried out before step (D):
Receiving the report command information from the serving base station to instruct the mobile station how and conditions to report the known information to the serving base station;
And said step (D) further comprises reporting said indication information to said serving base station according to the manner indicated by said report command information when a condition is satisfied. The method according to any one of claims 15 to 20,
Before step (A):
Reporting the channel related report information to the serving base station. The method of claim 21,
The channel related report information includes channel quality and / or carrier to noise ratio and / or received signal strength indication and / or location information of mobile stations. The method according to any one of claims 15 to 22,
The MIMO features include beamforming processing and / or codeword-weighting processing. The method according to any one of claims 15 to 23,
And said communication resources comprise a time resource and / or a frequency resource and / or a coding method. In a serving base station of a MIMO-based wireless communication network, a first providing apparatus for providing a communication scheme to one or more mobile stations served by a serving base station, comprising:
First signal transmitting means for sending one or more first detection signals in accordance with respective MIMO features to the one or more mobile stations, respectively, with one or more communication resources;
Obtaining indication information for obtaining from the one or more mobile stations information relating to the communication resources and / or indication information used to indicate MIMO features corresponding to recommended cooperative communication modes recommended by the one or more mobile stations. Way; And
And second providing means for scheduling at least one mobile station of the one or more mobile stations according to the indication information and providing a MIMO communication scheme for the at least one scheduled mobile station. The method of claim 25,
The first providing device is:
The one or more coordination of respective detection command information used to instruct one or more coordination base stations to send one or more second detection signals in accordance with respective MIMO features to the one or more mobile stations as the one or more communication resources. The first providing apparatus further comprising command sending means for sending to base stations. The method of claim 26,
Report obtaining means for obtaining channel related report information from the one or more mobile stations; And
And determining means for determining MIMO features corresponding to the communication resources and / or the one or more first detection signals in accordance with the channel related report information. The method of claim 27,
Further comprising command generating means for determining MIMO features corresponding to the communication resources and / or the one or more first detection signals, and generating one or more detection command information in accordance with the channel related report information, respectively; And the detection command information of the first communication apparatus includes respective MIMO features corresponding to the respective communication resources and / or the respective second detection signals. The method of claim 27 or 28,
The channel related report information of the one or more mobile stations reported by the one or more mobile stations includes a channel quality indication and / or a carrier to noise ratio and / or a received signal strength indication and / or location information of the one or more mobile stations. And a first providing device. The method according to any one of claims 26 to 29,
The command transmitting means also:
Measure to the one or more mobile stations to inform the one or more mobile stations to measure one or more detection signals with respective MIMO features sent by the one or more coordination base stations and the serving base station according to the one or more communication resources. Send command information,
A first providing apparatus, used to send report command information to the one or more mobile stations to indicate the scheme and condition to the one or more mobile stations for reporting the indication information to the serving base station. The method according to any one of claims 26 to 30,
When the one or more recommended cooperative communication modes apply that at least one of the serving base station and the coordination base stations simultaneously provide data services for the at least one scheduled mobile station, the second providing means also provides:
A first providing apparatus, according to the indication information, for providing for the scheduled mobile stations cooperative communication modes with communication resources and MIMO features corresponding to the one or more recommended cooperative communication modes. The method according to any one of claims 26 to 30,
When the one or more recommended cooperative communication modes apply that only the serving base station provides data services for the at least one scheduled mobile station and at least one coordinating base station suppresses interference to the scheduled mobile stations, The second providing means also comprises:
A first providing apparatus, used to provide, according to the indication information, an interference suppression communication scheme with communication resources and MIMO features corresponding to the recommended cooperative communication modes for the at least one scheduled mobile station. . The method according to any one of claims 25 to 32,
And the MIMO features include beamforming processing and / or codeword-weighting processing. The method according to any one of claims 25 to 33,
And the communication resources comprise a time resource and / or a frequency resource and / or a coding method. A first aiding apparatus for assisting a serving base station to provide a communication scheme to a mobile station served by coordination by a coordination base station in a MIMO-based wireless communication network:
And second signal transmitting means for sending one or more second detection signals in accordance with MIMO features to the one or more mobile stations as one or more communication resources. 36. The method of claim 35 wherein
Obtaining from the serving base station detection command information used to instruct the coordinating base stations to send one or more second detection signals according to respective MIMO features to the one or more mobile stations with corresponding one or more communication resources, A first aiding apparatus further comprising first command obtaining means. The method of claim 35 or 36,
And the detection signals in accordance with MIMO features comprise detection signals under beamforming processing and / or codeword-weighting processing. The method according to any one of claims 35 to 37,
And the communication resources comprise a time resource and / or a frequency resource and / or a coding method. A second aiding apparatus for assisting a serving base station to provide a communication scheme to a mobile station in a mobile station of a MIMO-based wireless communication network, comprising:
Signal acquiring means for obtaining at least one detection signals in accordance with MIMO features sent to one or more communication resources from one or more base stations including the serving base station;
Measuring means for measuring signal strength of at least one of the detection signals in accordance with MIMO features sent by one or more base stations to at least one of the one or more communication resources; And
The one or more indications according to the measured signal strength, the one or more indications used to indicate information related to the communication resources and / or one or more recommended cooperative communication modes recommended by the mobile station. A second aiding apparatus, comprising instruction information generating means for generating information. The method of claim 39,
And second indication information reporting means for reporting the indication information to the serving base station. 41. The method of claim 39 or 40 wherein
The signal strength of the first detection signal sent by the serving base station to a communication resource, detected by the mobile station, is above a first predefined threshold and is detected by the mobile station at least one of the corresponding resources. When the signal strength of the second detection signal sent by the coordination base station of is greater than or equal to a second predefined threshold, the one or more recommended cooperative communication modes indicate that the serving base station and the at least one coordination base station are for the mobile station. And providing said data services simultaneously and said indication information comprises said corresponding communication resources. 41. The method of claim 39 or 40 wherein
The signal strength of the first detection signal sent by the serving base station to a communication resource, detected by the mobile station, is above a third predefined threshold and is sent by each coordinating base station to corresponding resources; When the signal strength of the second detection signal is below a fourth predefined threshold, the one or more recommended cooperative communication modes indicate that only the serving base station provides data services for the mobile station and that at least one coordinating base station is selected by the mobile stations. Apply suppression of interference to the information and the indication information comprises the corresponding communication resources. 43. The method of claim 41 or 42,
The instruction information is:
A second aiding device, further comprising a signal strength of the first detection signal and / or the second detection signal on the corresponding communication resources. The method according to any one of claims 39 to 43,
Second command acquiring means for receiving measurement command information from the serving base station to instruct the mobile station one or more communication resources used to measure detection signals;
The signal obtaining means is also used to obtain a plurality of detection signals according to MIMO features sent from the plurality of base stations to the one or more communication resources in accordance with the one or more communication resources indicated by the measurement command information,
The second command acquiring means is also used to receive the report command information from the serving base station to instruct the mobile station a manner and condition of reporting the known information to the serving base station,
And the indication information reporting means is also used to report the indication information to the serving base station according to the manner indicated by the report command information when a condition is satisfied. The method according to any one of claims 39 to 44,
And second reporting means for reporting the channel related report information to the serving base station. The method of claim 45,
Wherein the channel related report information comprises channel quality and / or carrier to noise ratio and / or received signal strength indication and / or location information of mobile stations. The method according to any one of claims 39 to 46,
And the MIMO features include beamforming processing and / or codeword-weighting processing. The method according to any one of claims 39 to 47,
And the communication resources comprise a time resource and / or a frequency resource and / or a coding method.

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